Molecular diagnosis and biochemical studies of tick-borne diseases (anaplasmosis and babesiosis) in Aberdeen Angus Cattle in New Valley, Egypt

Abstract

Background and aim: Anaplasmosis and babesiosis are tick-borne diseases that threaten livestock production with subsequent considerable economic losses. This study was conducted to diagnose Anaplasma and Babesia infection using molecular techniques in imported Aberdeen Angus cattle imported from Uruguay to El-Kharga Oasis in New Valley, Egypt, and to investigate the effects of disease on some serum biochemical and oxidative stress parameters.

Materials and methods: Blood samples were collected from 31 cattle, 21 diseased and ten apparently normal, of varying ages and sex. The blood was used for the preparation of blood smears, polymerase chain reaction assay, and separation of serum for biochemical investigation. The experimental production farm at the Faculty of Agriculture, New Valley University, was infested with ticks and variable clinical manifestations during the period from December 2017 to March 2018. One calf died of a suspected blood parasite infection.

Results: The blood film examination revealed infection by blood parasites in 21 samples. Anaplasma marginale and Babesia bovis were identified in 12 and 14 samples, respectively. A total of 14 samples were examined by polymerase chain reaction (PCR) to make these identifications. Biochemical parameters showed significantly elevated serum alanine aminotransferase, aspartate aminotransferase, total bilirubin (T. Bil), and urea in blood from parasite-infected female cattle and male calves compared with controls. Increased serum total protein, globulin, and creatinine were recorded only in infected female cattle. The blood glucose level was significantly decreased in infected female cattle and male calves compared with controls. Furthermore, albumin and albumin/globulin ratio was significantly reduced in the infected female cattle. Oxidative stress profiles of infected animals showed a significant increase in serum nitric oxide and malondialdehyde, and both total antioxidant capacity and reduced glutathione (GSH) were significantly reduced in comparison with control animals.

Conclusion: The incidence of A. marginale and B. bovis infection is high in imported Aberdeen Angus cattle in New Valley Province. PCR methods provide a short-term assessment of disease. An extensive epidemiological survey, employing serology together with molecular genetic methods, monitoring of abundance and distribution of tick vectors, availability of vaccination programs, and tracking of animal transport is also needed for control of blood parasites.

Keywords: Aberdeen Angus cattle; Anaplasma marginal; Babesia bovis; oxidative stress.

Figure-1

Percent of clinically diseased cattle in relation to the age.

Figure-2

Showing tick infestation on the animal body (a-d) and pale mucus membrane (c and d).

Figure-3

Thin blood films stained with Giemsa stain: (a) RBCs infected with Anaplasma spp. (b and c) showing RBCs infected with Babesia spp.

Figure-4

Gel electrophoresis of PCR products of Anaplasma marginals, lane 1, 2, 3, 4, 6, 7, 8, 9, 10 in figure (a) are positive on bp 265 in female cows samples, and in figure (b) lane 3, 4, 5 are positive while lane 1 and 6 are negative, the amplified products prepared from positive blood samples except for two samples from calves were negative for Anaplasma marginale.

Figure-5

Gel electrophoresis of PCR products of Baabesia bovis, lane 1, 2, 3, 4, 6, 7, 8, 9, 10 in figure (a) are positive on bp 166 in cows samples while in figure (b) lane 1, 3, 4, 5, 6 are positive, the amplified products prepared from positive blood samples.